1. Field of the Invention
The present invention relates to an axle assembly to mount a wheel hub of a bicycle to a front fork or a suspension fork.
2. Related Background Art
A conventional axle assembly has a tubular body and a pair of holding members with a flange shape. In the conventional axle assembly, both ends of the tubular body are inserted into respective penetrating holes of a pair of shaft mounting portions (i.e. dropouts) furnished below a suspension fork; the respective holding members are screwed into both ends of the tubular body; and the holding members are used to nip and hold the pair of shaft mounting portions. The tubular body is thus installed on the pair of the shaft mounting portions. The tubular body rotatably supports a hub of a wheel.
The shaft mounting portions to mount such a conventional axle assembly are formed into two separate structures in order to enable the diameter of the penetrating holes of the shaft mounting portions to be reduced. After the tubular body is inserted into the penetrating hole, through integrating them by tightness of a fastening bolt so as to shrink a diameter of the penetrating hole, the tubular body is strongly fixed.
However, as stated above, when screwing the holding member or performing the tightening of the fastening bolt, there is a problem that not only is a wrench needed, but also time and exertion are needed for mounting and dismantling of the tubular body.
Recently, by furnishing slotted fingers for expanding a diameter at both ends of the tubular body, a fastening bar furnished on the tubular body can be moved by a lever operation of a cam lever. Diameters of the both ends of the tubular body via the slotted fingers are expanded by pressing a taper washer connected to the fastening bar into both ends of the tubular body. Peripheral surfaces of both ends of the tubular body are squeezed onto wall surfaces of the penetrating holes of the shaft mounting portions. Thus, the axle assembly having a structure in which the tubular body is installed on the shaft mounting portion is used practically.
This axle assembly can dismantle the tubular body from the shaft mounting portions by restoring the cam lever to an open position and taking off the taper washer from the fastening bar, and it has a comparatively simple structure for mounting and dismantling. However, since there are slotted fingers at both ends of the tubular body, there is a drawback that the strength of the tubular body becomes weak.